FaaS in-memory checkpoint restore

Abstract

A method for use in a computing device (100) for executing a FaaS process, said computing device (100) comprising a processor arrangement (110) and a memory (120), wherein the method comprises: receiving an event associated with a trigger, whereby an associated function is selected; obtaining page references to existing physical memory pages; initiating a process virtual memory table for a corresponding process; and executing the process based on the virtual memory table. And a method for use in a computing device (100) for performing a FaaS checkpoint operation, said computing device (100) comprising a processor arrangement (110) and a memory (120), wherein the method comprises: initiating a checkpoint is initiated; obtaining page references and storing them in a database virtual memory table in an in-memory database; replicating the page tables and indexes through a network; and storing changes to the in-memory database.

The invention claimed is: 
     
       1. A method for use in a computing device for executing a function-as-a-service (FaaS) process, wherein the method comprises:
 receiving an event associated with a trigger, whereby an associated function is selected; 
 obtaining page references to existing physical memory pages for the selected function, wherein the page references are arranged in one or more layers in an in-memory database, each of the one or more layers corresponding to changes made, in physical memory, to a process corresponding to the selected function, in a checkpointed environment; 
 initiating a process virtual memory table for the process corresponding to the selected function; and 
 executing the process based on the process virtual memory table; 
 
       wherein the initiation of the process virtual memory table is made by compiling the physical page memory references from at least one layer based on the requested indexes. 
     
     
       2. The method of  claim 1 , wherein the physical memory pages are stored in the in-memory database in an aligned manner and are thus ready to be used without having to be copied. 
     
     
       3. The method of  claim 1 , wherein the process virtual memory table is initiated with references to the existing physical memory pages. 
     
     
       4. The method of  claim 1 , wherein the method further comprises determining whether the process is a stateful process, and if so performing a checkpoint procedure. 
     
     
       5. A non-transitory computer-readable storage medium encoded with instructions that, when executed on a processor, perform the method according to  claim 1 . 
     
     
       6. A method for use in a computing device for performing a function-as-a-service (FaaS) checkpoint operation, wherein the method comprises:
 initiating a checkpoint; 
 obtaining page references and storing them in a database virtual memory table in an in-memory database; 
 replicating the page references and corresponding indexes through a network; and 
 storing changes to the in-memory database. 
 
     
     
       7. The method of  claim 6 , wherein the page references are arranged in layers and stored in the in-memory database. 
     
     
       8. A non-transitory computer-readable storage medium encoded with instructions that, when executed on a processor, perform the method according to  claim 6 . 
     
     
       9. A computing device for executing a function-as-a-service (FaaS) process, said computing device comprising a processor and a memory configured to:
 receive an event associated with a trigger, whereby an associated function is selected; 
 obtain page references to existing physical memory pages for the selected function, wherein the page references are arranged in one or more layers in an in-memory database, each of the one or more layers corresponding to changes made, in physical memory, to a process corresponding to the selected function, in a checkpointed environment; 
 initiate a process virtual memory table for the process corresponding to the selected function, by compiling the physical page memory references from at least one layer based on the requested indexes; and 
 execute the process based on the virtual memory table. 
 
     
     
       10. The computing device of  claim 9 , wherein the processor and memory are configured to access physical memory pages stored in the in-memory database in an aligned manner without having to copy the physical memory pages. 
     
     
       11. The computing device of  claim 9 , wherein the processor and memory are configured to initiate the process virtual memory table with references to the existing physical memory pages. 
     
     
       12. The computing device of  claim 9 , wherein the processor and memory are configured to determine whether the process is a stateful process, and if so perform a checkpoint procedure. 
     
     
       13. A computing device for performing a FaaS checkpoint operation, said computing device comprising a processor and a memory configured to:
 initiate a checkpoint; 
 obtain page references and storing them in a database virtual memory table in an in-memory database; 
 replicate the page references and corresponding indexes through a network; and 
 store changes to the in-memory database. 
 
     
     
       14. The computing device of  claim 13 , wherein the processor and memory are configured to arrange the page references in layers and store the page references in the in-memory database.